[mythtv-users] Fuzz in my video output

mooshie nsmith5 at umbc.edu
Tue Jun 20 04:26:10 UTC 2006


On Tue, 2006-06-20 at 00:04 -0400, mooshie wrote:
> On Mon, 2006-06-19 at 21:24 -0600, Brian Wood wrote:
> > On Jun 19, 2006, at 4:18 PM, Daniel Kristjansson wrote:
> > 
> > > On Mon, 2006-06-19 at 16:02 -0600, Brian Wood wrote:
> > >>>> It's probably being transmitted intentionally, it is data, in the
> > >>>> digital equivalent of the vertical blanking interval.
> > >>>> Usually most TVs overscan just a bit to prevent this showing up in
> > >>>> the picture.
> > >>> I'm viewing this on my monitor (Dell 24 inch 2405FPW LCD).. have
> > >>> you heard of it happening on monitors as well?
> > >> Especially on monitors, because they normally do not overscan at all.
> > >> I think Myth has some overscan settings in it, I'm not by my machine
> > >> at the moment and so can't check.
> > >> But I want to be sure this is what the problem is, I've never watched
> > >> QAM channels enough to notice if there is usually a bunch of data at
> > >> the top.
> > >> Can anybody else confirm this ? The description certainly sounds like
> > >> what data would look like in that position.
> > >
> > > I can confirm this is VBI data. This happens when the broadcaster or
> > > cable operator captures the entire frame of a NTSC stream. If you use
> > > either of the computer inputs on the monitor it won't do any overscan
> > > so you will see this data. MythTV can scale the video up a bit to hide
> > > this data. This one of the playback options and is called "overscan"
> > > in 0.19 and 0.19-fixes.

Just saw this line ^^, so forget that last email 




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